There’s plenty more fish in the sea, right?

Wrong. The sad estimate is that we have removed 90% of fish from our oceans through overfishing, which is not just pushing fish to the limit – but our own fellow humans as well.

Human Planet (BBC One) reveals how this overfishing is forcing divers in the Philippines to risk life and limb by setting and collecting nets at the bottom of the ocean. Spending hours at a time at depths of over 40 metres and breathing oxygen through a complicated web of make-shift, tangled tubes connected to a rusty compressor, one wrong move means certain death. Divers regularly suffer from the bends, which causes unbearable pain and can lead to paralysis and even death.

Equally dangerous, but much more controversial, is whaling. Watching a sperm whale being repeatedly harpooned to an exhausting and no doubt agonising eight-hour death doesn’t make for easy viewing. But to the hungry inhabitants of Lembata in Indonesia it is a 600 year-old means to survival, and will feed the whole village for months with every part of the whale used and appreciated. And, in their seas at least, sperm whales are no longer under threat.

From the distance of the sofa it’s easy to condemn the actions of these developing countries, but the sad reality is that we could do well to learn from their examples as we see in another powerful fight against unsustainable food practices with Hugh Fearnley-Whittingstall in Hugh’s Fish Fight (Channel 4). Astonishingly, EU laws aiming to protect dwindling populations such as cod mean that half of all the fish caught by North Sea fishermen have to be thrown back overboard – dead. It is a practice that has no environmental or economic sense, and leaves fishermen frustrated and powerless. As one puts it, “We’re not murderers – we don’t want to go out there and kill fish for the sake of it”.

With a warning of our seas being empty of fish within fifty years, this is a problem that needs addressing immediately, because the days have gone when there were plenty of fish in the sea.

For more info on the state of the fishing industry get over to the fine people who created knock out documentary End of the Line and join the campaign.

Human Planet is available on BBC iPlayer until 10/03/11

Hugh’s Fish Fight is available on 4oD until 05/02/11